cryptoxanthins and Arteriosclerosis

The oxidative modification of LDL is believed to be an initial step in atherosclerosis. Thus, antioxidative substances such as carotenoids may have a role in the prevention of coronary heart disease. We examined the susceptibility of LDL to Cu2+ oxidation in young adults before and after a single dose of beta-cryptoxanthin.. 1.3 mg of beta-cryptoxanthin was administered to 12 apparently healthy young volunteers. Six of the volunteers received esters, the other six free beta-cryptoxanthin. The plasma concentration of beta-cryptoxanthin and the susceptibility of LDL to copper-induced oxidation ex vivo in terms of the duration of lag time were measured before and 12 h after beta-cryptoxanthin ingestion.. A single dose of beta-cryptoxanthin significantly increased the mean plasma beta-cryptoxanthin concentration and the mean cholesterol adjusted beta-cryptoxanthin concentration by 117 and 133%, respectively. No effect on the length of lag time was assessed. However, in LDL isolated from plasma 12 h after beta-cryptoxanthin administration the lengths of lag time correlated significantly with the plasma beta-cryptoxanthin concentration and with the cholesterol adjusted beta-cryptoxanthin levels. The lag time did not differ significantly between volunteers who received esters and those who received the same dosage as free beta-cryptoxanthin. At both measuring points, smokers, male volunteers and women using oral contraceptives tended to exhibit lower beta-cryptoxanthin concentrations and lower cholesterol adjusted beta-cryptoxanthin concentrations as well as increased LDL oxidizability compared to nonsmokers and women not using oral contraceptives.. A single dose of beta-cryptoxanthin does not enhance the duration of LDL lag time ex vivo in healthy young subjects.

Topics: Adult; Arteriosclerosis; beta Carotene; Contraceptive Agents, Female; Copper; Cryptoxanthins; Esterification; Female; Humans; Lipoproteins, LDL; Male; Oxidation-Reduction; Smoking; Time Factors; Xanthophylls

Findings of observational studies suggest cardioprotective effects of antioxidant vitamins and carotenoids. However, recent meta-analyses failed to show the beneficial effects of supplemental intake of antioxidants on cardiovascular disease (CVD). We aimed to assess the association between CVD risk and β-cryptoxanthin in Japan, where Satsuma mandarin, a major source of β-cryptoxanthin, is widely consumed.. This was part of the Mikkabi cohort study. Surveys were conducted at baseline, in 2003 and 2005, and on follow-up in 2006, 2009, and 2013. We examined brachial-ankle pulse wave velocity (baPWV) with a high cut-off value set at 18.3 m s(-1). Hazard ratios (HR) and 95% confidence intervals for high baPWV were estimated using a Cox proportional hazards model with adjustment for potential confounders. A total of 635 participants with baPWV of less than 18.3 m s(-1) at baseline were included in the analysis. During the follow-up period of 57,921 person-months, 99 subjects developed high baPWV. After multivariate adjustment, the HR for high baPWV in the highest tertile compared with the lowest tertile was significantly low for β-cryptoxanthin, β-carotene, and total carotenoids. Serum concentrations of β-cryptoxanthin and β-carotene were higher in people who ate Satsuma mandarin frequently. Compared with <1/d intake of Satsuma mandarin, 3-4/d was associated with a low risk of high PWV.. This study indicated that β-cryptoxanthin and β-carotene derived from Satsuma mandarin are candidate micronutrients for preventing arteriosclerosis development. Further longitudinal and interventional studies will be required to validate the effect on CVD.

Topics: Adult; Aged; Ankle Brachial Index; Arteriosclerosis; beta Carotene; Beta-Cryptoxanthin; Citrus; Diet, Healthy; Female; Fruit; Health Surveys; Humans; Japan; Male; Middle Aged; Multivariate Analysis; Predictive Value of Tests; Prognosis; Prospective Studies; Pulse Wave Analysis; Risk Factors; Risk Reduction Behavior; Time Factors

Antioxidants are potentially beneficial in preventing vascular complications in diabetes because oxidative stress would be enhanced in such a condition and play an important role in vascular disorders. This study aimed to investigate whether brachial-ankle pulse wave velocity (baPWV) would be lower in the presence of high serum carotenoid concentrations stratified according to the glycemic state. A total of 297 men and 579 women between 30 and 70 years of age were analyzed cross-sectionally. Multivariate adjusted mean of baPWV in the highest tertile for beta-carotene (1386 cm/s) was lower than that in the lowest tertile (1432 cm/s) and that in the highest tertile for beta-cryptoxanthin (1382 cm/s) was lower than that in the middle tertile (1424 cm/s) in the case of normal fasting glucose. Similar inverse associations were observed in a group that included subjects with both impaired fasting glucose and diabetes, however, without statistical significance. The highest tertile of carotenoids was associated with a low risk for high baPWV (> or =1680 cm/s). Age, sex and glycemic state adjusted odds ratio was 0.35 (95% CI 0.20-0.60) for beta-carotene and 0.45 (0.27-0.77) for beta-cryptoxanthin. Multivariate adjustment did not alter the results. In conclusion, an inverse association of baPWV with beta-carotene and beta-cryptoxanthin was observed independently of the glycemic state.

Topics: Adult; Aged; Arteriosclerosis; beta Carotene; Biomarkers; Blood Flow Velocity; Blood Glucose; Brachial Artery; Cross-Sectional Studies; Cryptoxanthins; Diabetes Mellitus; Disease Progression; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prognosis; Pulsatile Flow; Retrospective Studies; Tibial Arteries; Xanthophylls

Interaction of peroxynitrite, the product of the reaction between nitric oxide and superoxide, with carotenes (lycopene, alpha-carotene, and beta-carotene) and oxocarotenoids (beta-cryptoxanthin, zeaxanthin, and lutein) was studied both in homogeneous solution and in human low-density lipoproteins (LDL). All carotenoids prevented the formation of rhodamine 123 from dihydrorhodamine 123 caused by peroxynitrite, suggesting that the carotenoids react with peroxynitrite. Oxocarotenoids were as effective as biothiols, known scavengers of peroxynitrite, whereas lycopene, alpha-carotene, and beta-carotene exhibited a considerably more pronounced effect. Moreover, peroxynitrite caused a loss of carotenoids in LDL as was revealed by HPLC. The concentration of peroxynitrite causing half-maximal loss of carotenoids in LDL ranged from 13 +/- 3 to 68 +/- 3 microM for lycopene and lutein, respectively. Again, oxocarotenoids were less reactive in this system. A correlation between efficiency of carotenoids in the competitive assay with dihydrorhodamine 123 and the concentration of peroxynitrite causing half-maximal loss of carotenoids in LDL was observed (r(2) = 0.91). These findings suggest that carotenoids can efficiently react with peroxynitrite and perform the role of scavengers of peroxynitrite in vivo.

Topics: Arteriosclerosis; beta Carotene; Carotenoids; Cryptoxanthins; Fluorescent Dyes; Free Radical Scavengers; Humans; In Vitro Techniques; Lipoproteins, LDL; Lutein; Lycopene; Nitrates; Rhodamine 123; Spectrometry, Fluorescence; Xanthophylls; Zeaxanthins